Rebecca Powell, PhD, right, with lab technician Alisa Fox
Could the dominant antibodies found in milk produced by women who have recovered from COVID-19 serve as a potent treatment for individuals—both adults and children—who now have the disease? Rebecca L. Powell, PhD, Assistant Professor of Medicine (Infectious Diseases), at the Icahn School of Medicine at Mount Sinai, is pursuing research to answer that question. An HIV researcher, Dr. Powell has also studied human breast milk extensively for its significant role in human health.
In early April, Dr. Powell began a large recruitment effort in New York City, collecting breast milk from 1,600 lactating women, 600 of whom had recovered after testing positive for COVID-19, and others who may have had the disease but were never tested and still produced antibodies.
Dr. Powell tested the milk in a small percentage of women and uploaded the study to the preprint server medRxiv. She reported that 14 out of 15 donors also had a significant level of COVID-19-reactive antibodies in their milk, which was enough to warrant moving forward with further investigation on a larger scale.
“There are a lot of reasons to believe this is worth exploring,” Dr. Powell says. “Milk antibodies are enriched with secretory antibodies and unique from those found in blood. Antibodies that are very dominant in milk are meant to be in the mucosal areas of the body, like the respiratory tract, and they would function well and be durable in this environment.” Secretory antibodies found in the gut and lungs are highly resistant and provide the first line of defense against many pathogens.
Since the SARS-CoV-2 virus, which leads to COVID-19, often begins in the respiratory tract, this is precisely the environment in which such antibodies would need to function.
Dr. Powell says the secretory antibodies from human milk could serve as a potential treatment in the same way blood antibodies do in antibody therapy, where the antibody-rich plasma from patients who have recovered from COVID-19 is transferred into patients with the disease. The Mount Sinai Health System was one of the first health providers in the nation to use this therapy.
The study’s data, Dr. Powell wrote, represents a “snapshot of what is likely a dynamic immune response. A much larger sample size and long-term follow-up study is needed to better understand SARS-CoV-2 immunity in milk, as well as whether a typical response is truly protective for breast-fed babies or if this response would generate sufficient antibodies to be purified and used therapeutically to treat COVID-19 illness.”
If a larger study ultimately supports the hypothesis, Dr. Powell says she envisions a potential therapy for patients with mild and severe cases of disease that could be administered directly into an individual’s lungs, much like the nebulizers that are used for treating asthma. She also says there is significant value in understanding how these secretory antibodies confer protection to breast-fed babies and for establishing a baseline for the protection they provide after vaccines become available.
“Unlike blood, human milk can be given daily and the supply can be increased by pumping,” Dr. Powell says. “There are likely many women in New York City who would donate their milk every day if they knew it could save lives.”